Comprehensive End-To-End Storage Area Network (san) Application Transport Service

1. A method for transmitting i/o requests on a data channel from a source to a destination, the data channel having a plurality of wavelength channels and a throughput, each wavelength channel having a distinct wavelength, the method comprising: multicasting i/o requests to the destination on each of the plurality of wavelength channels; multicasting data on each of the plurality of wavelength channels; recognizing a failure in one of the plurality of wavelength channels; continuing to transmit the data on another of the plurality of wavelength channels without synchronizing a new channel between the source and the destination, whereby an average latency between the source and the destination does not include a time needed to synchronize a new channel when failure occurs; adjusting the throughput during the multicasting by using buffer credits to determine a capacity of i/o requests that can be communicated between the source and the destination, to produce a consistent throughput; and managing data channel latency by submitting i/o requests to the destination during a predetermined time period associated with the average latency, including managing a size of a mid-span memory cache disposed between the source and the destination based on the average latency and the consistent throughput; determining the predetermined time period; submitting an i/o request to the source and to the destination; submitting additional i/o requests to the source and the destination during the predetermined time period; storing copies of the i/o request and the additional i/o requests in the mid-span memory cache disposed between the source and the destination; continuing submission of additional i/o requests to the source and the destination if an acknowledgement associated with the i/o request is received from the destination; resubmitting the i/o request and the additional i/o requests to the destination if an acknowledgement associated with the i/o request is not received from the destination and an acknowledgement associated with the i/o request is not received from the mid-span memory cache prior to completion of the predetermined time period; and instructing the mid-span memory cache to resubmit the i/o request and the additional i/o requests to the destination if an acknowledgement associated with the i/o request is not received from the destination and an acknowledgement associated with the i/o request is received from the mid-span cache prior to completion of the predetermined time period.

2. The method of claim 1 wherein the data channel is part of an optical network.

3. The method of claim 1 wherein the data channel is part of a packet-based network.

4. The method of claim 1 wherein the determining the predetermined time period comprises measuring an average round trip time for an average i/o request and an acknowledgement.

5. The method of claim 1 wherein the source halts submission of new i/o requests to the destination if the acknowledgement is not received from the destination.

6. A system for transmitting i/o requests on a data channel from a source to a destination, the data channel having a plurality of wave length channels and a throughput, each wavelength channel having a distinct wavelength, the system comprising: a storage application for multicasting i/o requests to the destination on each of the plurality of wavelength channels, to multicast data on each of the plurality of wavelength channels, to recognize a failure in one of the plurality of wavelength channels, and to continue to transmit the data on another of the plurality of wavelength channels without synchronizing a new channel between the source and the destination, whereby an average latency between the source and the destination does not include a time needed to synchronize a new channel when failure occurs; a storage protocol extension device for adjusting the throughput by using buffer credits to determine a capacity of data that can be communicated between the source and the destination to produce a consistent throughput; an application optimization device including a computer readable recording medium for managing data channel latency by submitting i/o requests to the destination during a predetermined time period associated with the average latency; the application optimization device including a mid-span memory cache, a size of the mid-span memory cache being managed based on the average latency and the consistent throughput, the mid-span memory cache being disposed between the source and the destination for storing copies of the i/o requests submitted to the destination during the predetermined time period, the application optimization device further being for instructing the mid-span memory cache to resubmit the i/o requests to the destination if an acknowledgement associated with the i/o requests is not received from the destination and an acknowledgement associated with the i/o requests is received from the mid-span cache prior to completion of the predetermined time period.

7. The system of claim 6 wherein the data channel is part of an optical network.

8. The system of claim 6 wherein the data channel is part of a packet-based network.

9. The system of claim 6 wherein the application optimization device further comprises at least one timer.

10. A system for transmitting i/o requests on a data channel from a source to a destination, the data channel having a plurality of wavelength channels and a throughput, each wavelength channel having a distinct wavelength, the system comprising: means for multicasting i/o requests to the destination on each of the plurality of wavelength channels; means for multicasting data on each of the plurality of wavelength channels; means for recognizing a failure in one of the plurality of wavelength channels; means for continuing to transmit the data on another of the plurality of wavelength channels without synchronizing a new channel between the source and the destination, whereby an average latency between the source and the destination does not include a time needed to synchronize a new channel when failure occurs; means for adjusting the throughput during the multicasting by using buffer credits to determine a capacity of data that can be communicated between the source and the destination, to produce a consistent throughput; means for managing data channel latency by submitting i/o requests to the destination during a predetermined time period associated with the average latency; and means for storing copies of the i/o requests during the predetermined time period between the source and the destination, the means for managing data channel latency further being for managing a size of a mid-span memory cache disposed between the source and the destination based on the average latency and the consistent throughput, and for instructing the means for storing copies to resubmit the i/o requests to the destination if an acknowledgement is not received from the destination and an acknowledgement is received from the means for storing copies prior to completion of the predetermined time period.

11. The system of claim 10 wherein the data channel is part of an optical network.

12. The system of claim 10 wherein the data channel is part of a packet-based network.

13. The system of claim 10 wherein the means for managing of the data channel latency further comprises: means for determining the predetermined time period by measuring an average round trip time for an average i/o request and an acknowledgement; means for submitting an i/o request to the source and to the destination; and means for submitting additional i/o requests to the source and the destination during the predetermined time period.

14. The system of claim 13 further comprising: means for resubmitting the i/o request and the additional i/o requests to the destination if the acknowledgement from the means for storing copies is not received prior to completion of the predetermined time period; and means for continuing submission of additional i/o requests to the source and the destination if the acknowledgement from the destination is received.

15. The system of claim 14 further comprising means for halting submission of new i/o requests to the source and the destination if the acknowledgement is not received.